He was born in Lincoln, the son of Jane (née Caparn or Capavor, died 1870) and Reverend John Hannah (1792–1867).
[2] He received his Master of Art degree in 1843 and in 1853 was made a Doctor of Canon Law (DCL) by the University of Edinburgh.
[2] Hannah abandoned teaching in 1870 to become vicar of the parish church of St Nicholas in Brighton,[2][3] upon the death of the Reverend Henry Michell Wagner.
[3] John Hannah was made rural dean of Brighton and Hove in 1871 and also given the prebendal stall of Sidlesham in Chichester Cathedral.
[2] In the same year, he founded the Pelham Institute—an Anglican "slum mission", working men's club and social venue in the Kemptown area of Brighton.